JPH08119247A - Thin wall plastic container and reinforced thin wall plastic container - Google Patents

Abstract

PURPOSE: To provide a thin wall plastic container whose weight is considerably reduced from the standpoint of the reduction of the amount of synthetic resin used and which, when discarded for disposal, can be broken into small pieces and, when filled with its liquid contents, can be prevented from the swelling of its body part. CONSTITUTION: In a thin wall plastic container having a vertical groove part 9 for folding purpose extending from its body part 4 to the bottom part 5, the container consists of a plurality of peripheral recess parts 4a and flat parts 4b arranged into the form of a bellows and vertical grooves 9 are formed in either recess parts 4a or flat parts 4b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic container, and more particularly to a plastic thin container which can be made thin to save resources and which can be easily disposed of after use.

[0002]

2. Description of the Related Art Conventionally, it has been widely used to obtain transparent and highly rigid containers by injection stretch blow molding of synthetic resins such as polyester and polypropylene. In the fields of beverage containers, toiletries, cosmetics, etc. in use. However, because containers made of synthetic resin have high calories burned and are bulky at the time of disposal, they are an environmental problem, and measures such as reducing the amount of synthetic resin used and making it reusable are needed. .

Therefore, for example, as disclosed in JP-A-6-219434, there has been proposed a plastic container in which a folding line for folding is formed from the body to the bottom in order to reduce the capacity at the time of disposal (FIG. 7). reference). This fold line is composed of an inverted Y-shaped concave line portion 25a and a convex line portion 25b parallel to the bottom surface, which allows the container to be easily folded and crushed after it becomes empty. Is. However, 0.1 mm to 0.
In the case of a thin container having a thickness of about 6 mm and a container having a circumferential recess in the body, there is a problem that the body swells when filled with the content liquid.

[0004]

In view of the reduction of the amount of synthetic resin used, the present invention can significantly reduce the weight of the container, can be crushed into small pieces at the time of disposal, and can be further filled in the container at the time of filling the content liquid. An object of the present invention is to provide a thin plastic container capable of preventing partial bulging.

[0005]

In order to solve the above-mentioned problems, the present invention is a thin-walled plastic container having a vertical groove portion for folding from a body portion to a bottom portion, the container having a plurality of circumferential recesses. A thin-walled plastic container comprising a flat portion, and the vertical groove portion being formed in only one of the concave portion and the flat portion. The container is preferably formed in a bellows shape in which a plurality of circumferential recesses and flat portions are alternately exposed. Further, it is preferable that the horizontal sectional shape of the container is substantially rectangular and the thickness of the body of the container is 0.1 mm to 0.6 mm. The container is preferably reinforced by a paper tube arranged so as to cover at least the peripheral surface of the body.

Materials for the thin-walled plastic container of the present invention include thermoplastic resins such as polyethylene terephthalate, polyester and polypropylene, high barrier resins such as copolymers containing acrylonitrile or methacrylonitrile as a main component, or thermosetting resins. It is possible to use, for example, a plastic resin blended with or laminated with a gas barrier resin such as saponified ethylene-vinyl acetate copolymer or aromatic nylon.

[0007]

According to the present invention, since the vertical groove portion for folding is formed in only one of the concave portion and the flat portion of the container body, as compared with the case where the vertical groove portion is formed over the entire length, The strength of the peripheral surface of the body is secured, and the body does not swell even when filled with the content liquid. When the container is laid down and crushed at the time of disposal, the point of action of the force is concentrated on the vertical groove portion, so that the body portion can be easily crushed with the vertical groove portion leading into the inside of the container.

If the container is formed in a bellows shape in which a plurality of circumferential concave portions and flat portions are alternately exposed, the container has excellent elasticity, so that the drop strength is improved. Also, the strength against deformation during compression is improved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. <First Example> The container body of the present example is a semitransparent thin-walled bottle produced by injection stretch blow molding using a polyethylene terephthalate resin. First, FIGS.
The thin-walled bottle will be described using. Thin bottle 1 has mouth 2
And a shoulder portion 3, a body portion 4 and a bottom portion 5.

As a molding procedure, first, a test tube-shaped molded product (hereinafter referred to as a preform) is molded by injection molding.
This preform is composed of a mouth portion and a tubular portion, and the body portion 4 and the bottom portion 5 of the bottle are formed by extending the tubular portion in the vertical and horizontal directions. Next, this preform was inserted into a blow mold, stretch-blown, and sufficiently stretched in the longitudinal and transverse directions to form a thin bottle 1. By using the injection stretch blow molding method as described above, the gas barrier property and the aroma retaining property,
Since the strength and the like are improved, the amount of resin used can be greatly reduced.

The molded thin-walled bottle 1 has a substantially quadrangular cross section, the shoulder portion 3 is gently inclined, and the bellows-like body portion 4 is formed.
A plurality of concave portions 4a and flat portions 4b are alternately exposed in the circumferential direction. Further, vertical grooves 9 are formed on the left and right side surfaces of the thin-walled bottle 1 only on the flat portion 4b to facilitate crushing. The vertical grooves 5 descend straight from the shoulder portion 3 and have an inverted Y shape at the lower end. It branches into a shape.

When the size and wall thickness of this thin bottle 1 were measured, the amount of resin used was 36 g, the full-filling capacity was 2200 ml, and the wall thickness of the body 3 was 150 μm to 300 μm.
And it was extremely thin. When the manufactured thin bottle 1 was filled with soy sauce, no swelling occurred in the body.

Next, a paper cylinder 6 for covering the body of the thin-walled bottle 1 was prepared. The paper tube 6 is a cardboard made of recycled paper, and is 300 to 400.
The blanks (not shown) of the paper cylinder 6 are printed and surface-treated with a thickness of g / m ² , and a front plate, a side plate, a back plate, and a side plate with a folding line interposed. The face plate and the glue allowance portion are connected in series, and the glue allowance portion is adhered to form a tubular shape.

When the paper cylinder 6 is formed in a tubular shape, the inner circumference is slightly larger than the outer diameter of the thin-walled bottle, and the space between the paper cylinder and the thin-walled bottle is preferably (preferably 1 mm or less). () Is set so that no gap is created.
As shown in FIG. 5, since the paper cylinder has a length covering from the lower end of the thin-walled bottle 1 to the upper end of the body portion 3, the buckling strength of the entire composite container 10 (reinforced thin-walled plastic container) Can be improved.

As a procedure for mounting the thin-walled bottle 1 on the paper cylinder 6, the paper cylinder 6 is first assembled from the blanks into a tubular shape, and then the hot-melt adhesive 8 in a molten state at high temperature is attached to the left and right side plates 7. 7 was attached to the inner surface of 7 at a point, and the thin bottle 1 filled with the content liquid was inserted from above the paper cylinder 6 in a short time (see FIG. 5).

The manufactured composite container 10 (reinforced thin-walled plastic container) was firmly integrated without the paper tube 6 coming off even in the vibration during transport or the drop test. Also, holding the composite container 10 upside down and repeatedly pouring out little by little, the thin bottle 1 did not deform until the end,
Moreover, the thin-walled bottle 1 could be used without coming off from the paper tube 6. After the use, when the thin-walled bottle 1 was pulled upward while the paper barrel 6 was strongly pressed down, the thin-walled bottle 1 and the paper barrel 6 were separated. When discarding, the paper tube 6 was folded flat and the body portion 3 of the thin bottle 1 was crushed by hand. Vertical groove 5
Since the ridges were formed, the action of the force was concentrated on the vertical groove portion 5, and the body portion 4 with the vertical groove portion 5 as the leading end entered the inside of the container and was easily crushed. Then, the paper tube 6 and the thin bottle 1 were separately discarded. The waste capacity could be made much smaller than before.

<Second Embodiment> A thin-walled bottle 11 was manufactured by using the same material as that of the first embodiment and the same molding method. As shown in FIG. 6, the thin-walled bottle 11 has a substantially quadrangular cross section, and is directly connected to the body portion from a flat shoulder portion 13. The bellows-shaped body portion 14 has a plurality of concave portions 14a and flat portions in the circumferential direction. 14b are exposed alternately. Further, on both the left and right side surfaces of the thin-walled bottle 11, vertical grooves 19 are provided to facilitate crushing.
Are formed only on the concave portion 14a.

When the size and wall thickness of the thin bottle 11 were measured, the amount of resin used was 36 g, the full-filling capacity was 2200 ml, and the wall thickness of the body 14 was 130 μm to 300 μm.
It was formed to be extremely thin with a thickness of μm. When the manufactured thin-walled bottle 11 was filled with soy sauce, no swelling occurred in the body. When the body portion 14 of the thin bottle 11 was crushed by hand, the vertical groove portion 19 was formed, so that the point of action of the force was concentrated on the vertical groove portion 19, and the body portion 14 was formed with the vertical groove portion 19 at the top. It crushed easily as it entered the inside of the container.

[0019]

According to the present invention, since the vertical groove portion for folding is formed only in either the concave portion or the flat portion of the container body portion, as compared with the case where the vertical groove portion is formed over the entire length. Therefore, the strength of the peripheral surface of the body is secured, and the body does not swell even when filled with the content liquid. When the container is laid down and crushed at the time of disposal, the point of action of the force is concentrated on the vertical groove portion, so that the body portion can be easily crushed with the vertical groove portion leading into the inside of the container. Therefore, it is an excellent container that can cope with environmental problems and is a practically excellent thin plastic container that can prevent the body part of the container from bulging.

Further, if the container is formed in a bellows shape in which a plurality of circumferential recesses and flat portions are alternately exposed, the container has excellent elasticity, so that the drop strength is improved. There is also an advantage that the strength against deformation during compression is also improved.

When the horizontal cross-sectional shape of the container is substantially rectangular and the thickness of the body of the container is 0.1 mm to 0.6 mm, the body swelling when the content liquid is filled becomes noticeable. Therefore, the effect according to the present invention is particularly effective.

When the container is reinforced by a paper tube arranged so as to cover at least the peripheral surface of the body, the bulging of the body of the container does not hinder the mounting work in the paper tube. There are advantages.

[Brief description of drawings]

FIG. 1 is a perspective view showing a thin bottle of a first embodiment.

2 is a side view of the thin bottle of FIG. 1. FIG.

3 is an enlarged sectional view of the thin bottle of FIG. 1 taken along line BB.

FIG. 4 is an enlarged cross-sectional view of the thin bottle of FIG. 1 taken along the line C-C.

FIG. 5 is a vertical cross-sectional view showing a state where a paper cylinder is attached to the thin-walled bottle of one embodiment.

FIG. 6 is a perspective view showing a thin bottle according to a second embodiment.

FIG. 7 is a perspective view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Thin bottle 2 ... Mouth part 3 ... Shoulder part 4 ... Body part 4a ... Recessed part 4b ... Flat part 5 ... Bottom part 6 ... Paper cylinder 7 ... Side plate 8 ... Hot melt adhesive 9 ... Vertical groove part 10 ... Composite container ( Reinforced thin-walled plastic container)

Claims (4)

[Claims] 1. A thin-walled plastic container having a vertical groove portion for folding from a body portion to a bottom portion, wherein the container is composed of a plurality of circumferential recesses and flat portions. Either of the recesses or the flat portions. A thin-walled plastic container characterized in that the vertical groove portion is formed only on one side. 2. The thin plastic container according to claim 1, wherein the container is formed in a bellows shape in which a plurality of circumferential recesses and flat portions are alternately exposed. 3. The container has a substantially rectangular horizontal cross section, and the body has a wall thickness of 0.1 mm to 0.6.
mm or claim 2 characterized in that
The thin-walled plastic container described in. 4. A reinforced thin walled container characterized in that the container according to any one of claims 1 to 3 is reinforced by a paper cylinder arranged so as to cover at least the peripheral surface of the body. Plastic container.